Improvement in reversible knob-latches



UNITED STATES PATENT OFFICE.

WILLIAM M. GRISooM AND FRANCIS eRoSSMAN, oE READING, PENNSYL- vANIA,ASSIGNoRs To SAID WILLIAM M. eRISooM.

IMPROVEMENT IN REVERSIBLE KNOB-LATCHES.

Specification forming part of Letters Patent N0. 186,556, dated January23, 1877; application tiled January 5, 1877.

` To all whom it 'may concern Be it known that we, WILLIAM-M. GRIS- coMand FRANCIS GRossMAN, of Reading, Pennsylvania, have invented certainImprovements in Reversible Latch-Locks, of which the following is aspecification:

The object of our invention is to so construct a reversible latch-lockthat the latch can only be reversed in the absence of the knob-spindlefrom the hub; and this object we attain in the manner which we will nowproceed todescribe, reference being had to the accompanying drawing, inwhich- Figure l is a front view of the lock, partly in section, and withthe face-plate removed; Fig. 2, a view of a portion of the same with theparts in a diiierent position; and Fig. 3, a

` sectional plan on the line l 2, Fig. 1.

A is the casing of the lock, in the lower portion of which are arrangedthe parts for operating the locking-bolt B; but as these parts aresimilar in construction and operation to those usuall5r employed inlocks of this class, description of them here will be unnecessary. D isthe latch-bolt, the spindle a y `of which is swiveled at the inner endto a yoke, E, which embraces the hub F on the knob-spindle b, and haslugs d d, on which usually act the arms e e on the hub, in order toretract the latch-bolt. In the present iustance, however, only oneoi1the arms e is securedto the hub, the other forming part of a lever, I,adapted to a slot cut in the hub F,

and pivoted, by means of a pin, i, to lugs m m on the same. In order tocheapen the lock this pin t is not riveted, being retained in place bythe opposite face-plates of the lock.

` The body of the lever I is cut away, so that when thelever is in theposition shown in Fig.

l it will not interfere with the continuity of the square opening in thehub for the receptionof the knob-spindle, this cutting away of the leverforming on the same a finger, s. Against a lug, t, on the short arm ofthe lever, bears one end of a bent spring, J, the opposite end of whichis hooked around a shoulder, .z', on the hub, so that` the risk ofaccidental displacement of the spring is prevented. The tendency of thespring J is to maintain the parts in the position shown `in Fig. 1, sothat the knob-spindle can be readily inserted into the opening in thehub. I

When the parts are in the position shown in Fig. l-that is, with theknob-spindle in position, and the latch-bolt in the recess in the edgeplate of the lock-any attempt to draw the Said latch-bolt forward, so asto free dle is not in place the withdrawal of the latchbolt will not beinterfered with.

We have shown our invention as applied-to a latch-bolt having anindependent. spring, y, for resisting the thrust against the outer endof the bolt; but it will be evident that it can be applied tolatch-bolts of a different construction with equal facility.

We claim as our inventionl. The combination, in a reversible latchlock,of the yoke E and its lugs d with the slotted hub F, its arm e, andpivoted lever I, as set forth.

2. The combination of the slotted hub F and its pivoted lever I, havinga finger, s, with a spring, J, as described.

3. The combination of the slotted hub F and its pivoted lever I with thebent spring J, bearing at one end against the lug t on the lever, andhooked at the other end, for adaptation to a shoulder, m, on the hub, asset forth. i

In testimony whereof we have signed our names to this specification inthe two subscribing witnesses.

WILLIAM M. GRISGOM. FRANCIS GROSSMAN. VWitnesses:

HARRY SMITH, S. D. DYER.

presence of

